git.sesse.net Git - movit/blob - effect_chain.cpp

   1 #define GL_GLEXT_PROTOTYPES 1
   2
   3 #include <stdio.h>
   4 #include <math.h>
   5 #include <string.h>
   6 #include <assert.h>
   7
   8 #include <algorithm>
   9 #include <set>
  10 #include <stack>
  11 #include <vector>
  12
  13 #include "util.h"
  14 #include "effect_chain.h"
  15 #include "gamma_expansion_effect.h"
  16 #include "gamma_compression_effect.h"
  17 #include "colorspace_conversion_effect.h"
  18 #include "input.h"
  19 #include "opengl.h"
  20
  21 EffectChain::EffectChain(float aspect_nom, float aspect_denom)
  22         : aspect_nom(aspect_nom),
  23           aspect_denom(aspect_denom),
  24           finalized(false) {}
  25
  26 Input *EffectChain::add_input(Input *input)
  27 {
  28         inputs.push_back(input);
  29
  30         Node *node = add_node(input);
  31         node->output_color_space = input->get_color_space();
  32         node->output_gamma_curve = input->get_gamma_curve();
  33         return input;
  34 }
  35
  36 void EffectChain::add_output(const ImageFormat &format)
  37 {
  38         output_format = format;
  39 }
  40
  41 Node *EffectChain::add_node(Effect *effect)
  42 {
  43         char effect_id[256];
  44         sprintf(effect_id, "eff%u", (unsigned)nodes.size());
  45
  46         Node *node = new Node;
  47         node->effect = effect;
  48         node->disabled = false;
  49         node->effect_id = effect_id;
  50         node->output_color_space = COLORSPACE_INVALID;
  51         node->output_gamma_curve = GAMMA_INVALID;
  52
  53         nodes.push_back(node);
  54         node_map[effect] = node;
  55         return node;
  56 }
  57
  58 void EffectChain::connect_nodes(Node *sender, Node *receiver)
  59 {
  60         sender->outgoing_links.push_back(receiver);
  61         receiver->incoming_links.push_back(sender);
  62 }
  63
  64 void EffectChain::replace_receiver(Node *old_receiver, Node *new_receiver)
  65 {
  66         new_receiver->incoming_links = old_receiver->incoming_links;
  67         old_receiver->incoming_links.clear();
  68
  69         for (unsigned i = 0; i < new_receiver->incoming_links.size(); ++i) {
  70                 Node *sender = new_receiver->incoming_links[i];
  71                 for (unsigned j = 0; j < sender->outgoing_links.size(); ++j) {
  72                         if (sender->outgoing_links[j] == old_receiver) {
  73                                 sender->outgoing_links[j] = new_receiver;
  74                         }
  75                 }
  76         }
  77 }
  78
  79 void EffectChain::replace_sender(Node *old_sender, Node *new_sender)
  80 {
  81         new_sender->outgoing_links = old_sender->outgoing_links;
  82         old_sender->outgoing_links.clear();
  83
  84         for (unsigned i = 0; i < new_sender->outgoing_links.size(); ++i) {
  85                 Node *receiver = new_sender->outgoing_links[i];
  86                 for (unsigned j = 0; j < receiver->incoming_links.size(); ++j) {
  87                         if (receiver->incoming_links[j] == old_sender) {
  88                                 receiver->incoming_links[j] = new_sender;
  89                         }
  90                 }
  91         }
  92 }
  93
  94 void EffectChain::insert_node_between(Node *sender, Node *middle, Node *receiver)
  95 {
  96         for (unsigned i = 0; i < sender->outgoing_links.size(); ++i) {
  97                 if (sender->outgoing_links[i] == receiver) {
  98                         sender->outgoing_links[i] = middle;
  99                         middle->incoming_links.push_back(sender);
 100                 }
 101         }
 102         for (unsigned i = 0; i < receiver->incoming_links.size(); ++i) {
 103                 if (receiver->incoming_links[i] == sender) {
 104                         receiver->incoming_links[i] = middle;
 105                         middle->outgoing_links.push_back(receiver);
 106                 }
 107         }
 108
 109         assert(middle->incoming_links.size() == middle->effect->num_inputs());
 110 }
 111
 112 void EffectChain::find_all_nonlinear_inputs(Node *node, std::vector<Node *> *nonlinear_inputs)
 113 {
 114         if (node->output_gamma_curve == GAMMA_LINEAR &&
 115             node->effect->effect_type_id() != "GammaCompressionEffect") {
 116                 return;
 117         }
 118         if (node->effect->num_inputs() == 0) {
 119                 nonlinear_inputs->push_back(node);
 120         } else {
 121                 assert(node->effect->num_inputs() == node->incoming_links.size());
 122                 for (unsigned i = 0; i < node->incoming_links.size(); ++i) {
 123                         find_all_nonlinear_inputs(node->incoming_links[i], nonlinear_inputs);
 124                 }
 125         }
 126 }
 127
 128 Effect *EffectChain::add_effect(Effect *effect, const std::vector<Effect *> &inputs)
 129 {
 130         assert(inputs.size() == effect->num_inputs());
 131         Node *node = add_node(effect);
 132         for (unsigned i = 0; i < inputs.size(); ++i) {
 133                 assert(node_map.count(inputs[i]) != 0);
 134                 connect_nodes(node_map[inputs[i]], node);
 135         }
 136         return effect;
 137 }
 138
 139 // GLSL pre-1.30 doesn't support token pasting. Replace PREFIX(x) with <effect_id>_x.
 140 std::string replace_prefix(const std::string &text, const std::string &prefix)
 141 {
 142         std::string output;
 143         size_t start = 0;
 144
 145         while (start < text.size()) {
 146                 size_t pos = text.find("PREFIX(", start);
 147                 if (pos == std::string::npos) {
 148                         output.append(text.substr(start, std::string::npos));
 149                         break;
 150                 }
 151
 152                 output.append(text.substr(start, pos - start));
 153                 output.append(prefix);
 154                 output.append("_");
 155
 156                 pos += strlen("PREFIX(");
 157
 158                 // Output stuff until we find the matching ), which we then eat.
 159                 int depth = 1;
 160                 size_t end_arg_pos = pos;
 161                 while (end_arg_pos < text.size()) {
 162                         if (text[end_arg_pos] == '(') {
 163                                 ++depth;
 164                         } else if (text[end_arg_pos] == ')') {
 165                                 --depth;
 166                                 if (depth == 0) {
 167                                         break;
 168                                 }
 169                         }
 170                         ++end_arg_pos;
 171                 }
 172                 output.append(text.substr(pos, end_arg_pos - pos));
 173                 ++end_arg_pos;
 174                 assert(depth == 0);
 175                 start = end_arg_pos;
 176         }
 177         return output;
 178 }
 179
 180 Phase *EffectChain::compile_glsl_program(
 181         const std::vector<Node *> &inputs,
 182         const std::vector<Node *> &effects)
 183 {
 184         assert(!effects.empty());
 185
 186         // Deduplicate the inputs.
 187         std::vector<Node *> true_inputs = inputs;
 188         std::sort(true_inputs.begin(), true_inputs.end());
 189         true_inputs.erase(std::unique(true_inputs.begin(), true_inputs.end()), true_inputs.end());
 190
 191         bool input_needs_mipmaps = false;
 192         std::string frag_shader = read_file("header.frag");
 193
 194         // Create functions for all the texture inputs that we need.
 195         for (unsigned i = 0; i < true_inputs.size(); ++i) {
 196                 Node *input = true_inputs[i];
 197
 198                 frag_shader += std::string("uniform sampler2D tex_") + input->effect_id + ";\n";
 199                 frag_shader += std::string("vec4 ") + input->effect_id + "(vec2 tc) {\n";
 200                 frag_shader += "\treturn texture2D(tex_" + input->effect_id + ", tc);\n";
 201                 frag_shader += "}\n";
 202                 frag_shader += "\n";
 203         }
 204
 205         for (unsigned i = 0; i < effects.size(); ++i) {
 206                 Node *node = effects[i];
 207
 208                 if (node->incoming_links.size() == 1) {
 209                         frag_shader += std::string("#define INPUT ") + node->incoming_links[0]->effect_id + "\n";
 210                 } else {
 211                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 212                                 char buf[256];
 213                                 sprintf(buf, "#define INPUT%d %s\n", j + 1, node->incoming_links[j]->effect_id.c_str());
 214                                 frag_shader += buf;
 215                         }
 216                 }
 217
 218                 frag_shader += "\n";
 219                 frag_shader += std::string("#define FUNCNAME ") + node->effect_id + "\n";
 220                 frag_shader += replace_prefix(node->effect->output_convenience_uniforms(), node->effect_id);
 221                 frag_shader += replace_prefix(node->effect->output_fragment_shader(), node->effect_id);
 222                 frag_shader += "#undef PREFIX\n";
 223                 frag_shader += "#undef FUNCNAME\n";
 224                 if (node->incoming_links.size() == 1) {
 225                         frag_shader += "#undef INPUT\n";
 226                 } else {
 227                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 228                                 char buf[256];
 229                                 sprintf(buf, "#undef INPUT%d\n", j + 1);
 230                                 frag_shader += buf;
 231                         }
 232                 }
 233                 frag_shader += "\n";
 234
 235                 input_needs_mipmaps |= node->effect->needs_mipmaps();
 236         }
 237         for (unsigned i = 0; i < effects.size(); ++i) {
 238                 Node *node = effects[i];
 239                 if (node->effect->num_inputs() == 0) {
 240                         node->effect->set_int("needs_mipmaps", input_needs_mipmaps);
 241                 }
 242         }
 243         frag_shader += std::string("#define INPUT ") + effects.back()->effect_id + "\n";
 244         frag_shader.append(read_file("footer.frag"));
 245
 246         // Output shader to a temporary file, for easier debugging.
 247         static int compiled_shader_num = 0;
 248         char filename[256];
 249         sprintf(filename, "chain-%03d.frag", compiled_shader_num++);
 250         FILE *fp = fopen(filename, "w");
 251         if (fp == NULL) {
 252                 perror(filename);
 253                 exit(1);
 254         }
 255         fprintf(fp, "%s\n", frag_shader.c_str());
 256         fclose(fp);
 257
 258         GLuint glsl_program_num = glCreateProgram();
 259         GLuint vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
 260         GLuint fs_obj = compile_shader(frag_shader, GL_FRAGMENT_SHADER);
 261         glAttachShader(glsl_program_num, vs_obj);
 262         check_error();
 263         glAttachShader(glsl_program_num, fs_obj);
 264         check_error();
 265         glLinkProgram(glsl_program_num);
 266         check_error();
 267
 268         Phase *phase = new Phase;
 269         phase->glsl_program_num = glsl_program_num;
 270         phase->input_needs_mipmaps = input_needs_mipmaps;
 271         phase->inputs = true_inputs;
 272         phase->effects = effects;
 273
 274         return phase;
 275 }
 276
 277 // Construct GLSL programs, starting at the given effect and following
 278 // the chain from there. We end a program every time we come to an effect
 279 // marked as "needs texture bounce", one that is used by multiple other
 280 // effects, every time an effect wants to change the output size,
 281 // and of course at the end.
 282 //
 283 // We follow a quite simple depth-first search from the output, although
 284 // without any explicit recursion.
 285 void EffectChain::construct_glsl_programs(Node *output)
 286 {
 287         // Which effects have already been completed in this phase?
 288         // We need to keep track of it, as an effect with multiple outputs
 289         // could otherwise be calculate multiple times.
 290         std::set<Node *> completed_effects;
 291
 292         // Effects in the current phase, as well as inputs (outputs from other phases
 293         // that we depend on). Note that since we start iterating from the end,
 294         // the effect list will be in the reverse order.
 295         std::vector<Node *> this_phase_inputs;
 296         std::vector<Node *> this_phase_effects;
 297
 298         // Effects that we have yet to calculate, but that we know should
 299         // be in the current phase.
 300         std::stack<Node *> effects_todo_this_phase;
 301
 302         // Effects that we have yet to calculate, but that come from other phases.
 303         // We delay these until we have this phase done in its entirety,
 304         // at which point we pick any of them and start a new phase from that.
 305         std::stack<Node *> effects_todo_other_phases;
 306
 307         effects_todo_this_phase.push(output);
 308
 309         for ( ;; ) {  // Termination condition within loop.
 310                 if (!effects_todo_this_phase.empty()) {
 311                         // OK, we have more to do this phase.
 312                         Node *node = effects_todo_this_phase.top();
 313                         effects_todo_this_phase.pop();
 314
 315                         // This should currently only happen for effects that are phase outputs,
 316                         // and we throw those out separately below.
 317                         assert(completed_effects.count(node) == 0);
 318
 319                         this_phase_effects.push_back(node);
 320                         completed_effects.insert(node);
 321
 322                         // Find all the dependencies of this effect, and add them to the stack.
 323                         std::vector<Node *> deps = node->incoming_links;
 324                         assert(node->effect->num_inputs() == deps.size());
 325                         for (unsigned i = 0; i < deps.size(); ++i) {
 326                                 bool start_new_phase = false;
 327
 328                                 // FIXME: If we sample directly from a texture, we won't need this.
 329                                 if (node->effect->needs_texture_bounce()) {
 330                                         start_new_phase = true;
 331                                 }
 332
 333                                 if (deps[i]->outgoing_links.size() > 1 && deps[i]->effect->num_inputs() > 0) {
 334                                         // More than one effect uses this as the input,
 335                                         // and it is not a texture itself.
 336                                         // The easiest thing to do (and probably also the safest
 337                                         // performance-wise in most cases) is to bounce it to a texture
 338                                         // and then let the next passes read from that.
 339                                         start_new_phase = true;
 340                                 }
 341
 342                                 if (deps[i]->effect->changes_output_size()) {
 343                                         start_new_phase = true;
 344                                 }
 345
 346                                 if (start_new_phase) {
 347                                         effects_todo_other_phases.push(deps[i]);
 348                                         this_phase_inputs.push_back(deps[i]);
 349                                 } else {
 350                                         effects_todo_this_phase.push(deps[i]);
 351                                 }
 352                         }
 353                         continue;
 354                 }
 355
 356                 // No more effects to do this phase. Take all the ones we have,
 357                 // and create a GLSL program for it.
 358                 if (!this_phase_effects.empty()) {
 359                         reverse(this_phase_effects.begin(), this_phase_effects.end());
 360                         phases.push_back(compile_glsl_program(this_phase_inputs, this_phase_effects));
 361                         this_phase_effects.back()->phase = phases.back();
 362                         this_phase_inputs.clear();
 363                         this_phase_effects.clear();
 364                 }
 365                 assert(this_phase_inputs.empty());
 366                 assert(this_phase_effects.empty());
 367
 368                 // If we have no effects left, exit.
 369                 if (effects_todo_other_phases.empty()) {
 370                         break;
 371                 }
 372
 373                 Node *node = effects_todo_other_phases.top();
 374                 effects_todo_other_phases.pop();
 375
 376                 if (completed_effects.count(node) == 0) {
 377                         // Start a new phase, calculating from this effect.
 378                         effects_todo_this_phase.push(node);
 379                 }
 380         }
 381
 382         // Finally, since the phases are found from the output but must be executed
 383         // from the input(s), reverse them, too.
 384         std::reverse(phases.begin(), phases.end());
 385 }
 386
 387 void EffectChain::output_dot(const char *filename)
 388 {
 389         FILE *fp = fopen(filename, "w");
 390         if (fp == NULL) {
 391                 perror(filename);
 392                 exit(1);
 393         }
 394
 395         fprintf(fp, "digraph G {\n");
 396         for (unsigned i = 0; i < nodes.size(); ++i) {
 397                 // Find out which phase this event belongs to.
 398                 int in_phase = -1;
 399                 for (unsigned j = 0; j < phases.size(); ++j) {
 400                         const Phase* p = phases[j];
 401                         if (std::find(p->effects.begin(), p->effects.end(), nodes[i]) != p->effects.end()) {
 402                                 assert(in_phase == -1);
 403                                 in_phase = j;
 404                         }
 405                 }
 406
 407                 if (in_phase == -1) {
 408                         fprintf(fp, "  n%ld [label=\"%s\"];\n", (long)nodes[i], nodes[i]->effect->effect_type_id().c_str());
 409                 } else {
 410                         fprintf(fp, "  n%ld [label=\"%s\" style=\"filled\" fillcolor=\"/accent8/%d\"];\n",
 411                                 (long)nodes[i], nodes[i]->effect->effect_type_id().c_str(),
 412                                 (in_phase % 8) + 1);
 413                 }
 414                 for (unsigned j = 0; j < nodes[i]->outgoing_links.size(); ++j) {
 415                         std::vector<std::string> labels;
 416
 417                         if (nodes[i]->outgoing_links[j]->effect->needs_texture_bounce()) {
 418                                 labels.push_back("needs_bounce");
 419                         }
 420                         if (nodes[i]->effect->changes_output_size()) {
 421                                 labels.push_back("resize");
 422                         }
 423
 424                         switch (nodes[i]->output_color_space) {
 425                         case COLORSPACE_INVALID:
 426                                 labels.push_back("spc[invalid]");
 427                                 break;
 428                         case COLORSPACE_REC_601_525:
 429                                 labels.push_back("spc[rec601-525]");
 430                                 break;
 431                         case COLORSPACE_REC_601_625:
 432                                 labels.push_back("spc[rec601-625]");
 433                                 break;
 434                         default:
 435                                 break;
 436                         }
 437
 438                         switch (nodes[i]->output_gamma_curve) {
 439                         case GAMMA_INVALID:
 440                                 labels.push_back("gamma[invalid]");
 441                                 break;
 442                         case GAMMA_sRGB:
 443                                 labels.push_back("gamma[sRGB]");
 444                                 break;
 445                         case GAMMA_REC_601:  // and GAMMA_REC_709
 446                                 labels.push_back("gamma[rec601/709]");
 447                                 break;
 448                         default:
 449                                 break;
 450                         }
 451
 452                         if (labels.empty()) {
 453                                 fprintf(fp, "  n%ld -> n%ld;\n", (long)nodes[i], (long)nodes[i]->outgoing_links[j]);
 454                         } else {
 455                                 std::string label = labels[0];
 456                                 for (unsigned k = 1; k < labels.size(); ++k) {
 457                                         label += ", " + labels[k];
 458                                 }
 459                                 fprintf(fp, "  n%ld -> n%ld [label=\"%s\"];\n", (long)nodes[i], (long)nodes[i]->outgoing_links[j], label.c_str());
 460                         }
 461                 }
 462         }
 463         fprintf(fp, "}\n");
 464
 465         fclose(fp);
 466 }
 467
 468 unsigned EffectChain::fit_rectangle_to_aspect(unsigned width, unsigned height)
 469 {
 470         if (float(width) * aspect_denom >= float(height) * aspect_nom) {
 471                 // Same aspect, or W/H > aspect (image is wider than the frame).
 472                 // In either case, keep width.
 473                 return width;
 474         } else {
 475                 // W/H < aspect (image is taller than the frame), so keep height,
 476                 // and adjust width correspondingly.
 477                 return lrintf(height * aspect_nom / aspect_denom);
 478         }
 479 }
 480
 481 // Propagate input texture sizes throughout, and inform effects downstream.
 482 // (Like a lot of other code, we depend on effects being in topological order.)
 483 void EffectChain::inform_input_sizes(Phase *phase)
 484 {
 485         // All effects that have a defined size (inputs and RTT inputs)
 486         // get that. Reset all others.
 487         for (unsigned i = 0; i < phase->effects.size(); ++i) {
 488                 Node *node = phase->effects[i];
 489                 if (node->effect->num_inputs() == 0) {
 490                         Input *input = static_cast<Input *>(node->effect);
 491                         node->output_width = input->get_width();
 492                         node->output_height = input->get_height();
 493                         assert(node->output_width != 0);
 494                         assert(node->output_height != 0);
 495                 } else {
 496                         node->output_width = node->output_height = 0;
 497                 }
 498         }
 499         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
 500                 Node *input = phase->inputs[i];
 501                 input->output_width = input->phase->output_width;
 502                 input->output_height = input->phase->output_height;
 503                 assert(input->output_width != 0);
 504                 assert(input->output_height != 0);
 505         }
 506
 507         // Now propagate from the inputs towards the end, and inform as we go.
 508         // The rules are simple:
 509         //
 510         //   1. Don't touch effects that already have given sizes (ie., inputs).
 511         //   2. If all of your inputs have the same size, that will be your output size.
 512         //   3. Otherwise, your output size is 0x0.
 513         for (unsigned i = 0; i < phase->effects.size(); ++i) {
 514                 Node *node = phase->effects[i];
 515                 if (node->effect->num_inputs() == 0) {
 516                         continue;
 517                 }
 518                 unsigned this_output_width = 0;
 519                 unsigned this_output_height = 0;
 520                 for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 521                         Node *input = node->incoming_links[j];
 522                         node->effect->inform_input_size(j, input->output_width, input->output_height);
 523                         if (j == 0) {
 524                                 this_output_width = input->output_width;
 525                                 this_output_height = input->output_height;
 526                         } else if (input->output_width != this_output_width || input->output_height != this_output_height) {
 527                                 // Inputs disagree.
 528                                 this_output_width = 0;
 529                                 this_output_height = 0;
 530                         }
 531                 }
 532                 node->output_width = this_output_width;
 533                 node->output_height = this_output_height;
 534         }
 535 }
 536
 537 // Note: You should call inform_input_sizes() before this, as the last effect's
 538 // desired output size might change based on the inputs.
 539 void EffectChain::find_output_size(Phase *phase)
 540 {
 541         Node *output_node = phase->effects.back();
 542
 543         // If the last effect explicitly sets an output size, use that.
 544         if (output_node->effect->changes_output_size()) {
 545                 output_node->effect->get_output_size(&phase->output_width, &phase->output_height);
 546                 return;
 547         }
 548
 549         // If not, look at the input phases and textures.
 550         // We select the largest one (by fit into the current aspect).
 551         unsigned best_width = 0;
 552         for (unsigned i = 0; i < phase->inputs.size(); ++i) {
 553                 Node *input = phase->inputs[i];
 554                 assert(input->phase->output_width != 0);
 555                 assert(input->phase->output_height != 0);
 556                 unsigned width = fit_rectangle_to_aspect(input->phase->output_width, input->phase->output_height);
 557                 if (width > best_width) {
 558                         best_width = width;
 559                 }
 560         }
 561         for (unsigned i = 0; i < phase->effects.size(); ++i) {
 562                 Effect *effect = phase->effects[i]->effect;
 563                 if (effect->num_inputs() != 0) {
 564                         continue;
 565                 }
 566
 567                 Input *input = static_cast<Input *>(effect);
 568                 unsigned width = fit_rectangle_to_aspect(input->get_width(), input->get_height());
 569                 if (width > best_width) {
 570                         best_width = width;
 571                 }
 572         }
 573         assert(best_width != 0);
 574         phase->output_width = best_width;
 575         phase->output_height = best_width * aspect_denom / aspect_nom;
 576 }
 577
 578 void EffectChain::sort_nodes_topologically()
 579 {
 580         std::set<Node *> visited_nodes;
 581         std::vector<Node *> sorted_list;
 582         for (unsigned i = 0; i < nodes.size(); ++i) {
 583                 if (nodes[i]->incoming_links.size() == 0) {
 584                         topological_sort_visit_node(nodes[i], &visited_nodes, &sorted_list);
 585                 }
 586         }
 587         reverse(sorted_list.begin(), sorted_list.end());
 588         nodes = sorted_list;
 589 }
 590
 591 void EffectChain::topological_sort_visit_node(Node *node, std::set<Node *> *visited_nodes, std::vector<Node *> *sorted_list)
 592 {
 593         if (visited_nodes->count(node) != 0) {
 594                 return;
 595         }
 596         visited_nodes->insert(node);
 597         for (unsigned i = 0; i < node->outgoing_links.size(); ++i) {
 598                 topological_sort_visit_node(node->outgoing_links[i], visited_nodes, sorted_list);
 599         }
 600         sorted_list->push_back(node);
 601 }
 602
 603 // Propagate gamma and color space information as far as we can in the graph.
 604 // The rules are simple: Anything where all the inputs agree, get that as
 605 // output as well. Anything else keeps having *_INVALID.
 606 void EffectChain::propagate_gamma_and_color_space()
 607 {
 608         // We depend on going through the nodes in order.
 609         sort_nodes_topologically();
 610
 611         for (unsigned i = 0; i < nodes.size(); ++i) {
 612                 Node *node = nodes[i];
 613                 if (node->disabled) {
 614                         continue;
 615                 }
 616                 assert(node->incoming_links.size() == node->effect->num_inputs());
 617                 if (node->incoming_links.size() == 0) {
 618                         assert(node->output_color_space != COLORSPACE_INVALID);
 619                         assert(node->output_gamma_curve != GAMMA_INVALID);
 620                         continue;
 621                 }
 622
 623                 ColorSpace color_space = node->incoming_links[0]->output_color_space;
 624                 GammaCurve gamma_curve = node->incoming_links[0]->output_gamma_curve;
 625                 for (unsigned j = 1; j < node->incoming_links.size(); ++j) {
 626                         if (node->incoming_links[j]->output_color_space != color_space) {
 627                                 color_space = COLORSPACE_INVALID;
 628                         }
 629                         if (node->incoming_links[j]->output_gamma_curve != gamma_curve) {
 630                                 gamma_curve = GAMMA_INVALID;
 631                         }
 632                 }
 633
 634                 // The conversion effects already have their outputs set correctly,
 635                 // so leave them alone.
 636                 if (node->effect->effect_type_id() != "ColorSpaceConversionEffect") {
 637                         node->output_color_space = color_space;
 638                 }
 639                 if (node->effect->effect_type_id() != "GammaCompressionEffect" &&
 640                     node->effect->effect_type_id() != "GammaExpansionEffect") {
 641                         node->output_gamma_curve = gamma_curve;
 642                 }
 643         }
 644 }
 645
 646 bool EffectChain::node_needs_colorspace_fix(Node *node)
 647 {
 648         if (node->disabled) {
 649                 return false;
 650         }
 651         if (node->effect->num_inputs() == 0) {
 652                 return false;
 653         }
 654
 655         // propagate_gamma_and_color_space() has already set our output
 656         // to COLORSPACE_INVALID if the inputs differ, so we can rely on that.
 657         if (node->output_color_space == COLORSPACE_INVALID) {
 658                 return true;
 659         }
 660         return (node->effect->needs_srgb_primaries() && node->output_color_space != COLORSPACE_sRGB);
 661 }
 662
 663 // Fix up color spaces so that there are no COLORSPACE_INVALID nodes left in
 664 // the graph. Our strategy is not always optimal, but quite simple:
 665 // Find an effect that's as early as possible where the inputs are of
 666 // unacceptable colorspaces (that is, either different, or, if the effect only
 667 // wants sRGB, not sRGB.) Add appropriate conversions on all its inputs,
 668 // propagate the information anew, and repeat until there are no more such
 669 // effects.
 670 void EffectChain::fix_internal_color_spaces()
 671 {
 672         unsigned colorspace_propagation_pass = 0;
 673         bool found_any;
 674         do {
 675                 found_any = false;
 676                 for (unsigned i = 0; i < nodes.size(); ++i) {
 677                         Node *node = nodes[i];
 678                         if (!node_needs_colorspace_fix(node)) {
 679                                 continue;
 680                         }
 681
 682                         // Go through each input that is not sRGB, and insert
 683                         // a colorspace conversion before it.
 684                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 685                                 Node *input = node->incoming_links[j];
 686                                 assert(input->output_color_space != COLORSPACE_INVALID);
 687                                 if (input->output_color_space == COLORSPACE_sRGB) {
 688                                         continue;
 689                                 }
 690                                 Node *conversion = add_node(new ColorSpaceConversionEffect());
 691                                 conversion->effect->set_int("source_space", input->output_color_space);
 692                                 conversion->effect->set_int("destination_space", COLORSPACE_sRGB);
 693                                 conversion->output_color_space = COLORSPACE_sRGB;
 694                                 insert_node_between(input, conversion, node);
 695                         }
 696
 697                         // Re-sort topologically, and propagate the new information.
 698                         propagate_gamma_and_color_space();
 699
 700                         found_any = true;
 701                         break;
 702                 }
 703
 704                 char filename[256];
 705                 sprintf(filename, "step3-colorspacefix-iter%u.dot", ++colorspace_propagation_pass);
 706                 output_dot(filename);
 707                 assert(colorspace_propagation_pass < 100);
 708         } while (found_any);
 709
 710         for (unsigned i = 0; i < nodes.size(); ++i) {
 711                 Node *node = nodes[i];
 712                 if (node->disabled) {
 713                         continue;
 714                 }
 715                 assert(node->output_color_space != COLORSPACE_INVALID);
 716         }
 717 }
 718
 719 // Make so that the output is in the desired color space.
 720 void EffectChain::fix_output_color_space()
 721 {
 722         Node *output = find_output_node();
 723         if (output->output_color_space != output_format.color_space) {
 724                 Node *conversion = add_node(new ColorSpaceConversionEffect());
 725                 conversion->effect->set_int("source_space", output->output_color_space);
 726                 conversion->effect->set_int("destination_space", output_format.color_space);
 727                 conversion->output_color_space = output_format.color_space;
 728                 connect_nodes(output, conversion);
 729         }
 730 }
 731
 732 bool EffectChain::node_needs_gamma_fix(Node *node)
 733 {
 734         if (node->disabled) {
 735                 return false;
 736         }
 737
 738         // Small hack since the output is not an explicit node:
 739         // If we are the last node and our output is in the wrong
 740         // space compared to EffectChain's output, we need to fix it.
 741         // This will only take us to linear, but fix_output_gamma()
 742         // will come and take us to the desired output gamma
 743         // if it is needed.
 744         //
 745         // This needs to be before everything else, since it could
 746         // even apply to inputs (if they are the only effect).
 747         if (node->outgoing_links.empty() &&
 748             node->output_gamma_curve != output_format.gamma_curve &&
 749             node->output_gamma_curve != GAMMA_LINEAR) {
 750                 return true;
 751         }
 752
 753         if (node->effect->num_inputs() == 0) {
 754                 return false;
 755         }
 756
 757         // propagate_gamma_and_color_space() has already set our output
 758         // to GAMMA_INVALID if the inputs differ, so we can rely on that,
 759         // except for GammaCompressionEffect.
 760         if (node->output_gamma_curve == GAMMA_INVALID) {
 761                 return true;
 762         }
 763         if (node->effect->effect_type_id() == "GammaCompressionEffect") {
 764                 assert(node->incoming_links.size() == 1);
 765                 return node->incoming_links[0]->output_gamma_curve != GAMMA_LINEAR;
 766         }
 767
 768         return (node->effect->needs_linear_light() && node->output_gamma_curve != GAMMA_LINEAR);
 769 }
 770
 771 // Very similar to fix_internal_color_spaces(), but for gamma.
 772 // There is one difference, though; before we start adding conversion nodes,
 773 // we see if we can get anything out of asking the sources to deliver
 774 // linear gamma directly. fix_internal_gamma_by_asking_inputs()
 775 // does that part, while fix_internal_gamma_by_inserting_nodes()
 776 // inserts nodes as needed afterwards.
 777 void EffectChain::fix_internal_gamma_by_asking_inputs(unsigned step)
 778 {
 779         unsigned gamma_propagation_pass = 0;
 780         bool found_any;
 781         do {
 782                 found_any = false;
 783                 for (unsigned i = 0; i < nodes.size(); ++i) {
 784                         Node *node = nodes[i];
 785                         if (!node_needs_gamma_fix(node)) {
 786                                 continue;
 787                         }
 788
 789                         // See if all inputs can give us linear gamma. If not, leave it.
 790                         std::vector<Node *> nonlinear_inputs;
 791                         find_all_nonlinear_inputs(node, &nonlinear_inputs);
 792                         assert(!nonlinear_inputs.empty());
 793
 794                         bool all_ok = true;
 795                         for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
 796                                 Input *input = static_cast<Input *>(nonlinear_inputs[i]->effect);
 797                                 all_ok &= input->can_output_linear_gamma();
 798                         }
 799
 800                         if (!all_ok) {
 801                                 continue;
 802                         }
 803
 804                         for (unsigned i = 0; i < nonlinear_inputs.size(); ++i) {
 805                                 nonlinear_inputs[i]->effect->set_int("output_linear_gamma", 1);
 806                                 nonlinear_inputs[i]->output_gamma_curve = GAMMA_LINEAR;
 807                         }
 808
 809                         // Re-sort topologically, and propagate the new information.
 810                         propagate_gamma_and_color_space();
 811
 812                         found_any = true;
 813                         break;
 814                 }
 815
 816                 char filename[256];
 817                 sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
 818                 output_dot(filename);
 819                 assert(gamma_propagation_pass < 100);
 820         } while (found_any);
 821 }
 822
 823 void EffectChain::fix_internal_gamma_by_inserting_nodes(unsigned step)
 824 {
 825         unsigned gamma_propagation_pass = 0;
 826         bool found_any;
 827         do {
 828                 found_any = false;
 829                 for (unsigned i = 0; i < nodes.size(); ++i) {
 830                         Node *node = nodes[i];
 831                         if (!node_needs_gamma_fix(node)) {
 832                                 continue;
 833                         }
 834
 835                         // Special case: We could be an input and still be asked to
 836                         // fix our gamma; if so, we should be the only node
 837                         // (as node_needs_gamma_fix() would only return true in
 838                         // for an input in that case). That means we should insert
 839                         // a conversion node _after_ ourselves.
 840                         if (node->incoming_links.empty()) {
 841                                 assert(node->outgoing_links.empty());
 842                                 Node *conversion = add_node(new GammaExpansionEffect());
 843                                 conversion->effect->set_int("source_curve", node->output_gamma_curve);
 844                                 conversion->output_gamma_curve = GAMMA_LINEAR;
 845                                 connect_nodes(node, conversion);
 846                         }
 847
 848                         // If not, go through each input that is not linear gamma,
 849                         // and insert a gamma conversion before it.
 850                         for (unsigned j = 0; j < node->incoming_links.size(); ++j) {
 851                                 Node *input = node->incoming_links[j];
 852                                 assert(input->output_gamma_curve != GAMMA_INVALID);
 853                                 if (input->output_gamma_curve == GAMMA_LINEAR) {
 854                                         continue;
 855                                 }
 856                                 Node *conversion = add_node(new GammaExpansionEffect());
 857                                 conversion->effect->set_int("source_curve", input->output_gamma_curve);
 858                                 conversion->output_gamma_curve = GAMMA_LINEAR;
 859                                 insert_node_between(input, conversion, node);
 860                         }
 861
 862                         // Re-sort topologically, and propagate the new information.
 863                         propagate_gamma_and_color_space();
 864
 865                         found_any = true;
 866                         break;
 867                 }
 868
 869                 char filename[256];
 870                 sprintf(filename, "step%u-gammafix-iter%u.dot", step, ++gamma_propagation_pass);
 871                 output_dot(filename);
 872                 assert(gamma_propagation_pass < 100);
 873         } while (found_any);
 874
 875         for (unsigned i = 0; i < nodes.size(); ++i) {
 876                 Node *node = nodes[i];
 877                 if (node->disabled) {
 878                         continue;
 879                 }
 880                 assert(node->output_gamma_curve != GAMMA_INVALID);
 881         }
 882 }
 883
 884 // Make so that the output is in the desired gamma.
 885 // Note that this assumes linear input gamma, so it might create the need
 886 // for another pass of fix_internal_gamma().
 887 void EffectChain::fix_output_gamma()
 888 {
 889         Node *output = find_output_node();
 890         if (output->output_gamma_curve != output_format.gamma_curve) {
 891                 Node *conversion = add_node(new GammaCompressionEffect());
 892                 conversion->effect->set_int("destination_curve", output_format.gamma_curve);
 893                 conversion->output_gamma_curve = output_format.gamma_curve;
 894                 connect_nodes(output, conversion);
 895         }
 896 }
 897
 898 // Find the output node. This is, simply, one that has no outgoing links.
 899 // If there are multiple ones, the graph is malformed (we do not support
 900 // multiple outputs right now).
 901 Node *EffectChain::find_output_node()
 902 {
 903         std::vector<Node *> output_nodes;
 904         for (unsigned i = 0; i < nodes.size(); ++i) {
 905                 Node *node = nodes[i];
 906                 if (node->disabled) {
 907                         continue;
 908                 }
 909                 if (node->outgoing_links.empty()) {
 910                         output_nodes.push_back(node);
 911                 }
 912         }
 913         assert(output_nodes.size() == 1);
 914         return output_nodes[0];
 915 }
 916
 917 void EffectChain::finalize()
 918 {
 919         // Output the graph as it is before we do any conversions on it.
 920         output_dot("step0-start.dot");
 921
 922         // Give each effect in turn a chance to rewrite its own part of the graph.
 923         // Note that if more effects are added as part of this, they will be
 924         // picked up as part of the same for loop, since they are added at the end.
 925         for (unsigned i = 0; i < nodes.size(); ++i) {
 926                 nodes[i]->effect->rewrite_graph(this, nodes[i]);
 927         }
 928         output_dot("step1-rewritten.dot");
 929
 930         propagate_gamma_and_color_space();
 931         output_dot("step2-propagated.dot");
 932
 933         fix_internal_color_spaces();
 934         fix_output_color_space();
 935         output_dot("step4-output-colorspacefix.dot");
 936
 937         // Note that we need to fix gamma after colorspace conversion,
 938         // because colorspace conversions might create needs for gamma conversions.
 939         // Also, we need to run an extra pass of fix_internal_gamma() after
 940         // fixing the output gamma, as we only have conversions to/from linear.
 941         fix_internal_gamma_by_asking_inputs(5);
 942         fix_internal_gamma_by_inserting_nodes(6);
 943         fix_output_gamma();
 944         output_dot("step7-output-gammafix.dot");
 945         fix_internal_gamma_by_asking_inputs(8);
 946         fix_internal_gamma_by_inserting_nodes(9);
 947
 948         output_dot("step10-final.dot");
 949
 950         // Construct all needed GLSL programs, starting at the output.
 951         construct_glsl_programs(find_output_node());
 952
 953         output_dot("step11-split-to-phases.dot");
 954
 955         // If we have more than one phase, we need intermediate render-to-texture.
 956         // Construct an FBO, and then as many textures as we need.
 957         // We choose the simplest option of having one texture per output,
 958         // since otherwise this turns into an (albeit simple)
 959         // register allocation problem.
 960         if (phases.size() > 1) {
 961                 glGenFramebuffers(1, &fbo);
 962
 963                 for (unsigned i = 0; i < phases.size() - 1; ++i) {
 964                         inform_input_sizes(phases[i]);
 965                         find_output_size(phases[i]);
 966
 967                         Node *output_node = phases[i]->effects.back();
 968                         glGenTextures(1, &output_node->output_texture);
 969                         check_error();
 970                         glBindTexture(GL_TEXTURE_2D, output_node->output_texture);
 971                         check_error();
 972                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 973                         check_error();
 974                         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 975                         check_error();
 976                         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F_ARB, phases[i]->output_width, phases[i]->output_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
 977                         check_error();
 978
 979                         output_node->output_texture_width = phases[i]->output_width;
 980                         output_node->output_texture_height = phases[i]->output_height;
 981                 }
 982                 inform_input_sizes(phases.back());
 983         }
 984
 985         for (unsigned i = 0; i < inputs.size(); ++i) {
 986                 inputs[i]->finalize();
 987         }
 988
 989         assert(phases[0]->inputs.empty());
 990
 991         finalized = true;
 992 }
 993
 994 void EffectChain::render_to_fbo(GLuint dest_fbo, unsigned width, unsigned height)
 995 {
 996         assert(finalized);
 997
 998         // Save original viewport.
 999         GLuint x = 0, y = 0;
1000
1001         if (width == 0 && height == 0) {
1002                 GLint viewport[4];
1003                 glGetIntegerv(GL_VIEWPORT, viewport);
1004                 x = viewport[0];
1005                 y = viewport[1];
1006                 width = viewport[2];
1007                 height = viewport[3];
1008         }
1009
1010         // Basic state.
1011         glDisable(GL_BLEND);
1012         check_error();
1013         glDisable(GL_DEPTH_TEST);
1014         check_error();
1015         glDepthMask(GL_FALSE);
1016         check_error();
1017
1018         glMatrixMode(GL_PROJECTION);
1019         glLoadIdentity();
1020         glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0);
1021
1022         glMatrixMode(GL_MODELVIEW);
1023         glLoadIdentity();
1024
1025         if (phases.size() > 1) {
1026                 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
1027                 check_error();
1028         }
1029
1030         std::set<Node *> generated_mipmaps;
1031
1032         for (unsigned phase = 0; phase < phases.size(); ++phase) {
1033                 // See if the requested output size has changed. If so, we need to recreate
1034                 // the texture (and before we start setting up inputs).
1035                 inform_input_sizes(phases[phase]);
1036                 if (phase != phases.size() - 1) {
1037                         find_output_size(phases[phase]);
1038
1039                         Node *output_node = phases[phase]->effects.back();
1040
1041                         if (output_node->output_texture_width != phases[phase]->output_width ||
1042                             output_node->output_texture_height != phases[phase]->output_height) {
1043                                 glActiveTexture(GL_TEXTURE0);
1044                                 check_error();
1045                                 glBindTexture(GL_TEXTURE_2D, output_node->output_texture);
1046                                 check_error();
1047                                 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F_ARB, phases[phase]->output_width, phases[phase]->output_height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
1048                                 check_error();
1049                                 glBindTexture(GL_TEXTURE_2D, 0);
1050                                 check_error();
1051
1052                                 output_node->output_texture_width = phases[phase]->output_width;
1053                                 output_node->output_texture_height = phases[phase]->output_height;
1054                         }
1055                 }
1056
1057                 glUseProgram(phases[phase]->glsl_program_num);
1058                 check_error();
1059
1060                 // Set up RTT inputs for this phase.
1061                 for (unsigned sampler = 0; sampler < phases[phase]->inputs.size(); ++sampler) {
1062                         glActiveTexture(GL_TEXTURE0 + sampler);
1063                         Node *input = phases[phase]->inputs[sampler];
1064                         glBindTexture(GL_TEXTURE_2D, input->output_texture);
1065                         check_error();
1066                         if (phases[phase]->input_needs_mipmaps) {
1067                                 if (generated_mipmaps.count(input) == 0) {
1068                                         glGenerateMipmap(GL_TEXTURE_2D);
1069                                         check_error();
1070                                         generated_mipmaps.insert(input);
1071                                 }
1072                                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
1073                                 check_error();
1074                         } else {
1075                                 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
1076                                 check_error();
1077                         }
1078
1079                         std::string texture_name = std::string("tex_") + input->effect_id;
1080                         glUniform1i(glGetUniformLocation(phases[phase]->glsl_program_num, texture_name.c_str()), sampler);
1081                         check_error();
1082                 }
1083
1084                 // And now the output.
1085                 if (phase == phases.size() - 1) {
1086                         // Last phase goes to the output the user specified.
1087                         glBindFramebuffer(GL_FRAMEBUFFER, dest_fbo);
1088                         check_error();
1089                         glViewport(x, y, width, height);
1090                 } else {
1091                         Node *output_node = phases[phase]->effects.back();
1092                         glFramebufferTexture2D(
1093                                 GL_FRAMEBUFFER,
1094                                 GL_COLOR_ATTACHMENT0,
1095                                 GL_TEXTURE_2D,
1096                                 output_node->output_texture,
1097                                 0);
1098                         check_error();
1099                         glViewport(0, 0, phases[phase]->output_width, phases[phase]->output_height);
1100                 }
1101
1102                 // Give the required parameters to all the effects.
1103                 unsigned sampler_num = phases[phase]->inputs.size();
1104                 for (unsigned i = 0; i < phases[phase]->effects.size(); ++i) {
1105                         Node *node = phases[phase]->effects[i];
1106                         node->effect->set_gl_state(phases[phase]->glsl_program_num, node->effect_id, &sampler_num);
1107                         check_error();
1108                 }
1109
1110                 // Now draw!
1111                 glBegin(GL_QUADS);
1112
1113                 glTexCoord2f(0.0f, 0.0f);
1114                 glVertex2f(0.0f, 0.0f);
1115
1116                 glTexCoord2f(1.0f, 0.0f);
1117                 glVertex2f(1.0f, 0.0f);
1118
1119                 glTexCoord2f(1.0f, 1.0f);
1120                 glVertex2f(1.0f, 1.0f);
1121
1122                 glTexCoord2f(0.0f, 1.0f);
1123                 glVertex2f(0.0f, 1.0f);
1124
1125                 glEnd();
1126                 check_error();
1127
1128                 for (unsigned i = 0; i < phases[phase]->effects.size(); ++i) {
1129                         Node *node = phases[phase]->effects[i];
1130                         node->effect->clear_gl_state();
1131                 }
1132         }
1133 }